Method and apparatus for document validation

ABSTRACT

The invention provides a unique method and apparatus to validate documents. Particularly, the method comprises forming a developable area on the surface of a paper document, scanning the surface before development, causing development, and then scanning the same surface after development so that a before and after scanning must meet predetermined signal acceptance criteria to provide a validation. The development is achieved by some external force or media acting on the document, with the document responding to such force or media to change its physical characteristics. The apparatus to achieve this sequence of method steps consists of appropriate testing areas incorporating radiant energy sources and appropriately responsive photocells, or other detectors, plus the development area and a validation circuit, all operating in cooperation to measure the surface appearance or characteristics before and after development of one or more portions of the document. Development normally is contemplated to be by heat, pressure, moisture, fumes, electric current, or the like.

United States Patent Bayha Mar. 28, 1972 METHOD AND APPARATUS FOR DOCUMENT VALIDATION Primary Examiner-James W, Lawrence Assistant Examiner-D. C. Nelms Attorney0ldham & Oldham [72] Inventor: Jack E. Bayha, l 1753 Sperry Road,

Chesterland, Ohio 44026 57] ABSTRAQT [22] Filed: 1970 The invention provides a unique method and apparatus to 21 APPL 47 validate documents. Particularly, the method comprises forming a developable area on the surface of a paper document, scanning the surface before development, causing develop- [52] US. Cl. ..250/219 DR, 250/67, 250/219 DQ mem and then Scanning the Same Surface after development [51] Ill!- Cl. ..G01I1 21/30 so that a before and after scanning must meet predetermined [58] new of Search 150/221 219 219 signal acceptance criteria to provide a validation. The

250/219 219 219 219 219 development is achieved by some external force or media act- 219 zg 219 23 ing on the document, with the document responding to such 10 35 H l6 l 340/14 force or media to change its physical characteristics. The apparatus to achieve this sequence of method steps consists of [56] References cued appropriate testing areas incorporating radiant energy sources UNITED STATES PATENTS and appropriately responsive photocell s, or other detectors,

plus the development area and a validation circuit, all operat- 3,428,819 Qu nn ing in cooperation to measure the urface appearance or Ra chman characteristics before and after development of one or more portions of the document Development normally is contem. 3,004,702 10/1961 Kl'anl -250/223 plated to be by heat, pressure, moisture, fumes, electric cur- 3,473,035 10/1969 Gardner..... ..250/223 rem, or the i 3,048,697 8/1962 Cavanaugh ..250/71 9 Claims, 4 Drawing Figures RADIENT ENERGY RADIENT EN '1 W2 20 $1440 28 DOCUMENT TESTING DOCUMENT TESTING 22 AREA DEvli-ilgllMENT AREA REJECT i -|6 I8 I6 I I 1 PHOTOCELL VALIDATION PHOTOCELL DOCUMENT DETECTION CIRCUIT DETECTION STORAGE 5m 24 REJECT SIGNAL 26 VALIDATION SIGNAL a PATENTEnmes m2 3,652,862

RADIENT ENERGY IO l4 j E TQ '20 /l4u 2s x '22 DOCUMENT DOCUMENT TESTING DEVELOPMENT TESTING ARE I AREA AREA RFJECT l6 I8 I60 30 g PHOTOCELL VALIDATION PHOTOCELL DOCUMENT DETECTION CIRCUIT DETECTION STORAGE am 24\- REJECT SlGNAL F|G 26 VALIDATION SIGNAL 44 TEST 4O DEVELOP TEST Heat 42 \%Llqhi H 42 so ilj o TEST A CLEAR -'E} 1 Z 1 1 AREA Fm I "--'fi Photocell Ham Phoiocgll 'gsn 5 DARKENED AREA FIG.Z E 52 ACCEPT L lREJEcT e2 6 64 & Ugh-i $3 1 DEVELOPMENT AREA H I 66 156 Photocells 7o--\\ FIG-3 6?6*;\

W TESTING 5 3 AREA INVENTOR.

JACK E. BAYHA MJM ATTORNEYS METHOD AND APPARATUS FOR DOCUMENT VALIDATION Heretofore, it has been known that there have been many and various ways to validate documents, but these normally have been limited to examining the documents as they are and not performing some positive action on the document itself to provide validation or authentication. Further, these prior art systems have not utilized any positive means to insure cancellation of the document so that further use would be impossible, or a similar type of indication to show that the document has been used. 7 7w 7 U Therefore, it is a general object of the invention to provide apparatus and a method to validate documents, and particularly documents designed for automatic validation where validation under some circumstances will render the document useful only once. i w v A further object of the invention is to provide a method for validation of documents which will require as much specialized knowledge and technique as possible to prevent compromise of the validation.

A further object of the invention is to provide an apparatus for document validation which utilizes a test of a portion of the document, a development of the document to allow a subsequent test of the same portion of the document, with a difference detected in the tests being necessary within prescribed limits to achieve proper validation. A A

The aforesaid objects of the invention and other objects which will become apparent as the description proceeds are achieved by providing a process for validating a paper document which comprises the following sequential steps:

a. Inspecting at least one portion of the paper document by scanning it with radiant energy and detecting the radiant energy with a photocell responsive to the radiant energy,

b. Determining if the signal from the photocell falls within a predetermined acceptable range,

c. Producing a change in the physical appearance or characteristics of at least one said portion of the document, w w W d. Inspecting at least the same one portion of the paper document by scanning it with radiant energy and detecting the radiant energy with a photocell responsive to the radiant energy, and

e. Determining whether the detection by both photocells or other detectors in steps (a) and (d) fall within predetermined -mwa... ..-,.a.a u

The apparatus to achieve the objects of the invention comprises a document testing area, means to move the document into the testing area, means to test a portion of the document with radiant energy, means to develop the document by applying an external force to the document to change the physical appearance or characteristics of said one portion of the document, means to test at least said one portion of the document again after its development, and a validation circuit receiving the results of both tests to determine if predetermined changes have taken place and indicate validation.

For a better understanding of the invention reference Sh ul b h Q he 4999mm"yit stawuaewl F IG. 1 is a block diagram schematic of the apparatus necessary to achieve the preferred embodiment of the invention;

FIG. 2 is a schematic illustration of the method steps necessary to achieve the process of the invention;

FIG. 3 illustrates one typical type of configuration which could be utilized on the document to operate within the steps of FIG. 2; and

FIG. 4 is a scheinatic diagram of a typical apparatus to comprise the validation circuit. A

The general technique behind the invention is accomplished by designing documents for automatic validation by making the documents require as much specialized knowledge and technique as possible. It is further desirable to have a method of rendering the document useful only once under some circumstances. Specifically, I wish to treat an area or areas on the document with a substance which changes appearance or physical characteristics either due to chemical, physical or thermal external influence. This change occurs practically immediately as soon as the external influence is applied.

Typical examples of such things are the color change which occurs by physical means when you press on 3M action paper (as made by the 3M Company of Minneapolis, Minn.), the instant reaction to heat by thermofax was material (as made by 3M and Tempil Division of Big 3 Industries Gas and Equipment Company of New York) which is irreversible, or that of some other substances which on cooling revert to the invisible form, the irreversible act of turning purple when exposed to ammonia, or black or red, etc., of diazo materials, or the persistance of a phospher such as zinc sulphide, which emits light after ultra violet excitation.

The general technique for utilizing the above general approach to my invention is by utilizing this effect in a secure fashion by examining the document as it enters an apparatus with the photocell and determining it is plain white, as a typical example, remembering this fact in some typical validation circuit, and looking at the document again, after it has been subject to an external force which force is defined herein as being either chemical, physical, thermal, or electrical external influence. Typically, the paper of the document could be treated with potassium iodide, with the passage of electric current therethrough causing it to turn dark.

Hence, in general hereinafter, I am defining an invention which includes a developable area of a special type, in a security document, which may or may not cancel the value of the document which is accomplished by first examining the area, then developing it, then examining it again, and comparing the prior and subsequent results received by examining such area.

A typical apparatus to achieve the objects of the invention is illustrated in FIG. 1. Specifically, this illustrates a document 10 passing into a testing area 12 where radiant energy 14 is directed onto the document for either reflective or transmissive detection by a photocell 16. The signal from the photocell is sent to an appropriate validation circuit 18. Typically, the document may be inserted into the testing area 12 by being placed on a conveyor and moved thereon, or being placed on a tray, and slid into position and locked for the testing with the radiant energy source, which is the type described in my prior U.S. Pat. Nos. 3,360,658 and 3,457,421, or it may simply be pushed by hand into the area where the testing takes place. I contemplate that the testing may occur either while the document is stationary or while it is moving, with this being quite easily controlled by the activation of appropriate microswitches indicating the position of the document, or any other means well known to those skilled in the art.

The document 10 then proceeds into a document development area indicated by numeral 20 where the document is developed by the external force comprising any of the chemical, physical, thermal, or electrical techniques generally specified above. Actually, the type of development will depend upon the particular configuration and characteristics of the document which have been previously incorporated into the document onto one or more portions thereof.

The document next proceeds into a second testing area 22 which in essence is similar to the area 12 as the invention contemplates the same type of radiant energy photocell detection test will be performed by radiant energy source 14a and photocell detection 16a, respectively. The signal from photocell detection 16a is again passed into the validation circuit 18, and this then cooperates to produce a reject signal 24, or a validation signal 26 which cooperate with the movement of the document from the testing area either into a reject path 28, or a document storage bin 30, or the like.

While the apparatus to achieve the objects of the invention described above with reference to FIG. 1 illustrates a document 10 moving through a plurality of separate areas 12, 20 and 22, it should be understood that these particular areas could all be combined into the same physical space, with actually the same testing apparatus comprising the radiant energy and photocell detection being the same for the separate areas 12 and 22 of FIG. 1. This is readily apparent to one skilled in the art, if it is desired to conserve space, or perform all these tests with the document at rest in the same physical area, and can be easily implemented.

PROCESS FIG. 2 illustrates the process steps of the invention as achieved by the apparatus of FIG. 1. Specifically, a document 40 includes a preprocessed area 42, which normally appears clear before such area has been physically acted upon or developed. The first step in the process then involves the use of a radiant energy source such as light 44 directing its radiant energy onto the document 40 through the area 42 to be detected by a photocell 46. The output of the photocell is sent to a validation circuit 48. Naturally, with area 42 being clear, the output of photocell 46 will represent a clear signal or one at a high energy level.

The next step in the process then involves the application of an external force to the document, and particularly the portion of the document which has been pretreated or preranged to respond to such external force. In the instance shown in FIG. 2, a typical application might be heat which causes a change in the physical appearance of area 42 to the darkened configuration illustrated. The heat may actually be provided by the light 44 in a single testing unit configuration. This is the development stage or step, and as indicated above, may take place in the same area with sequential actuation of respective components to achieve the desired steps.

The development stage is then followed by another test of the area 42 with this being performed by a light radiant energy source 50 cooperating with a photocell 52 to again send a signal to the validation circuit 48. Naturally, because the test of area 42 now indicates a darkened configuration, the energy level detected by photocell 52 will be substantially reduced, and it is a comparison of the proper high intensity signal from photocell 46 and a proportional lower intensity signal from photocell 52 that will provide proper activation of the validation circuit to indicate an acceptance or rejection of the particular document being tested. This is more fully defined hereinafter.

Further, it should be readily understandable from the sequence of steps illustrated in FIG. 2 that the darkened area 42 may be permanently darkened which would in effect render the document 40 unusable in the future, or in particular instances, the area may revert back to its original state upon removal of the outside physical force which is causing the change in the physical appearance or characteristics of the document being tested or validated. Hence, this provides a destructive characteristic readily as a part of the validation as selectively desired. It is a simple matter for anyone skilled in the art to properly choose the type of reaction and characteristics of the reacting area or portion of the document so as to provide a permanent change or temporary change depending upon the results desired.

The steps shown in FIG. 3 simply illustrate a document 60 with a clear test area 62 formed in a criss-cross shape, which illustrates that after development, a radiant energy source 64 must produce activation of four photocells indicated generally by numeral 66 before proper signal actuation to the validation circuit would be possible while not activating cells 67. Naturally, any particular configuration to the test area is possible, and it should also be understood that any number of test areas could be utilized with perhaps each one being activated by one or more different physical forces according to the type of forces set forth above.

The actual characteristics of the validation circuit are readily apparent to anyone skilled in the art, as the specific configuration of this circuit could take many forms. Hence, the particular circuit comprising the validation circuit is not believed to comprise a critical part of the invention in view of the overall objectives required, but any approach to appropriately distinguish between predetermined signal levels, and not indicate validation until both these signal levels have been achieved in sequential periods, would satisfactorily meet the objects of the invention. A typical circuit might include a threshold gate able to pass only high intensity signals indicating a clear, and with the passage of this signal actuating a flipflop from one state to another. A similar type of gate having a sensitivity to a lower intensity would be actuated only by the proper signal from the second test, and upon this proper signal, would actuate the flip-flop back to its original position, which return to the original position would indicate satisfactory completion of the test and actuate validation and acceptance. However, it is obvious, that many other suitable circuits to perform this sequential test and acceptance would readily be apparent to those skilled in the art.

For example, the circuit of FIG. 4 includes a potential 70 with actuating switch 71, a radiant energy heater lamp 72, a radiant energy detector 74, an amplifier 76, a validation indicator 78, and relays and 82 cooperating with switches 84 and 86 respectively. In this circuit a document in the testing area is heat sensitive. Upon activation of the circuit by switch 71, light 72 is energized. The energy from lamp 72 is initially detected by cell 74 as it passes through a clear area of the document. The amplifier signal, if valid, is sufficient to actuate relays 80 and 82, thus actuating both switches 84 and 86 from the normal solid line positions indicated. Relay 82 is a latching type so it will stay locked up upon proper initial actuation as long as any electrical signal remains. The heat from light 72 will then darken the heat sensitive portion of the document adjacent thereto in the testing area. When this has properly darkened, the signal from amplifier 76 will have decreased to a predetermined value to cause regular relay 80 to drop out allowing switch 84 to return to its solid line position thereby actuating validation indicator 78.

Thus, it is seen that the initial signal must be proper to actuate both relays, and the subsequent signal must diminish to a proper value to drop relay 80 out. In this manner both signals are automatically compared to a predetermined standard and to themselves so that an excellent reliability for validation is achieved.

In some instances, it may be desirable to incorporate an actual heating element into the structure if the light 72 will not change the physical appearance of the document quickly enough. For this purpose I employ a transparent heater 73 which is positioned immediately adjacent the document 90, as seen in FIG. 4. This type of heater, about the size of a postage stamp, is made by Thermal Systems of Los Angeles, California. This heater used with Thermo-Fax heat sensitive paper will turn the color thereof from white to dark within less than one second when the heater is contacting the document.

Also, I contemplate that a plurality of separate areas could be sensitive to development with any one or more of these areas being sensed according to the techniques of my invention to indicate validation. This is a similar confusing situation to a would be counterfeiter as is present in my patent on scrip number U.S. Pat. No. 3,471,172.

Also, I contemplate that the physical characteristics of the document be changed which in addition to changes in visual appearance, might include changes in electrical conductivity, thickness, porosity, density, reflectivity, and the like. Further, while scanning the portion or portions of the document has been described above as being accomplished with radiant light energy, scanning could be understood to include passage of electrical current through the document, measurement of density, porosity, thickness, magnetic qualities, and the like with appropriate apparatus, all known and understood by those skilled in the art.

Hence, it is seen that the objects of the invention have been achieved by providing the treatment of an area or areas on a paper document which treatment changes the physical appearance or characteristics of the document either due to chemical, physical, thermal, and/or electrical external influence. This in effect includes a developable area on the document which may or may not cancel the value of the document, and which may or may not make it capable of being reused.

While in accordance with the Patent Statutes only one best known embodiment of the invention has been illustrated and described in detail, it is to be particularly understood that the invention is not limited thereto or thereby, but that the inventive scope is defined in the appended claims.

What is claimed is:

1. A process for validating a paper document which comprises the following sequential steps:

a. Inspecting at least one portion of the paper document by scanning it and detecting at least the portion scanned with an apparatus responsive thereto to produce a signal thereof,

b. Determining if the signal from the apparatus falls within a first predetermined acceptable range,

0. Producing a change in the physical characteristics of at least said portion of the paper document,

d. inspecting at least said portion of the paper document again by scanning it and detecting the area with apparatus responsive thereto to produce a signal thereof, and

e. Determining if the signal from the apparatus falls within a second predetermined acceptable range, and depending upon the determination indicating a validation or rejection of the document.

2. A process according to claim 1 wherein the document remains in the same location for each sequential step, and steps (a) and (d) are both performed with the same inspection apparatus and by the same technique.

3. A process according to claim 1 where the step producing a change in physical characteristics of the document produces a permanent physical change therein.

4. A process according to claim 1 where the scanning is with radiant energy and detection is with a photocell responsive thereto.

5. A process for validating a paper document which comprises the following sequential steps:

a. Treating at least one portion of a paper document with a temperature sensitive indicator substance of the type that changes from high to low light reflectivity and transmissability by changing from a clear color to a dark color by the application of heat to said substance,

b. Inspecting said treated portions of the paper document by measuring the intensity of light transmitted through said treated portions of the paper document from a light source by means of a photocell array comprising one or more photocells,

c. Determining if electrical signals from the photocell array produced by light transmission through said treated portions of the paper document fall within a first predetermined acceptable range,

d. Producing a change in the light transmissability of said treated portions of the paper document by applying heat to said treated portions,

e. inspecting said treated portions of the paper document again by measuring the intensity of light transmitted through said treated portions of the paper document from a light source by means of a photocell array,

. Determining if electrical signals from the photocell array produced by light transmission through said treated portions of the paper document fall within a second predetermined acceptable range, and depending upon the determination indicating a validation or rejection of the document.

6. A process according to claim 5 where the document remains in the same location for each sequential step, and steps (b) and (e) are both performed with the same inspection apparatus and by the same technique.

7. A process according to claim 5 where the step producing a change in light transmissability of the treated portions of the document produces a permanent chan e therein.

8. A process according to claim where the light transmitted through the treated portions of the paper document is of wavelengths invisible to the human eye and detection is with a photocell array responsive thereto.

9. A process according to claim 5 where inspection is made of the treated portions of a paper document by reflectance of light from the treated portions onto a photocell array responsive thereto. 

1. A process for validating a paper document which comprises the following sequential steps: a. Inspecting at least one portion of the paper document by scanning it and detecting at least the portion scanned with an apparatus responsive thereto to produce a signal thereof, b. Determining if the signal from the apparatus falls within a first predetermined acceptable range, c. Producing a change in the physical characteristics of at least said portion of the paper document, d. Inspecting at least said portion of the paper document again by scanning it and detecting the area with apparatus responsive thereto to produce a signal thereof, and e. Determining if the signal from the apparatus falls within a second predetermined acceptable range, and depending upon the determination indicating a validation or rejection of the document.
 2. A process according to claim 1 wherein the document remains in the same location for each sequential step, and steps (a) and (d) are both performed witH the same inspection apparatus and by the same technique.
 3. A process according to claim 1 where the step producing a change in physical characteristics of the document produces a permanent physical change therein.
 4. A process according to claim 1 where the scanning is with radiant energy and detection is with a photocell responsive thereto.
 5. A process for validating a paper document which comprises the following sequential steps: a. Treating at least one portion of a paper document with a temperature sensitive indicator substance of the type that changes from high to low light reflectivity and transmissability by changing from a clear color to a dark color by the application of heat to said substance, b. Inspecting said treated portions of the paper document by measuring the intensity of light transmitted through said treated portions of the paper document from a light source by means of a photocell array comprising one or more photocells, c. Determining if electrical signals from the photocell array produced by light transmission through said treated portions of the paper document fall within a first predetermined acceptable range, d. Producing a change in the light transmissability of said treated portions of the paper document by applying heat to said treated portions, e. Inspecting said treated portions of the paper document again by measuring the intensity of light transmitted through said treated portions of the paper document from a light source by means of a photocell array, f. Determining if electrical signals from the photocell array produced by light transmission through said treated portions of the paper document fall within a second predetermined acceptable range, and depending upon the determination indicating a validation or rejection of the document.
 6. A process according to claim 5 where the document remains in the same location for each sequential step, and steps (b) and (e) are both performed with the same inspection apparatus and by the same technique.
 7. A process according to claim 5 where the step producing a change in light transmissability of the treated portions of the document produces a permanent change therein.
 8. A process according to claim 5 where the light transmitted through the treated portions of the paper document is of wavelengths invisible to the human eye and detection is with a photocell array responsive thereto.
 9. A process according to claim 5 where inspection is made of the treated portions of a paper document by reflectance of light from the treated portions onto a photocell array responsive thereto. 